Solar Air Heater

[Shadow]

Heres my version of a Solar heater. Its alot  the same as most others out there.

 Except for the absorber material. I used channel metal, its 3 inch wide by 1 1/2 high. I never have found out the gauge of it, heavier than pop cans but still cuts easy with snips.It was used in a suspended ceiling in office building. I got a truckload free so I'm trying to find uses for it. I think I succeeded.

The glass is tempered glass out of patio doors. I dont think I would take them apart again. Wayy to much work. I would use the polycarbonate stuff next time.

Its 76 inches by 84 inches, the return air feeds in the bottom header up through all the channels to the top header and hot air goes out  the 2 left channells which are seperate from the rest. It works awesome!  It exceeds my expectations by a mile.

Its not exactly winter yet but, it was 16 C (about 61 F) the in line fan(5 inch) in the basement comes on at 120 degrees.It came on at 9:30 am and at noon it was 225 degrees inside the heater! So today I added a second inline fan on the hot side to try to use more of the heat.

I really noticed how long it retains its heat, clouds dont have any effect on it for quite a length of time.I think theres something to be said for slightly heavier absorber material.And I think the 1 1/2 inch air space, along with the 1 inch space between glass and absorber is a good match.Just my unscientific opionon so far.

I havent finished building my mount yet to mount it close up on the house. It will go up close to the overhead window. I'm experimenting with angles I think its about 60 degrees right now.

[Shadow]

WOOHOO !! First time I've got photos to work!

[BrianSmith]

Your heater looks great.  I like the channel idea. 

[MattM]

Judging by the primer on the back its probably an aluminum material.  If its steel then I'd have to take an educated guess and day probably 24 gauge.  If its aluminum the material looks like .032 stock.  Lighter stock aluminum tends to have a lighter shade of primer, depending on the manufacturer.  Is it Firestone/una clad material?

[Shadow]

I'll see if I can find a name or number on it, its definately a steel type. As it shows rust on some of the end cuts and where it got scratched. i'll take piece to town and get a gauge on it.

It sure gets hot, I hooked up a second inline fan today and got alot more heat! But it still didnt lower the inside of the box temp very much.

The glass gets fairly hot to the touch which tells me I'm losing alot of heat but what does a guy do?  Bigger fan?(s)

[windy]

Shadow,
Could I ask what type of paint did you use on the channels?
windy

[Shadow]

I used a can of Flat black high heat paint I think its good for 1000 degrees. I'll get the name of it tomorrow I bought it at Home Hardware here in Canada. I rolled 3 coats on. Then used Barbecue paint in an aerosol can to touch up any places the roller didnt get.

[MattM]

I've always wanted to do something like your box only in a vaccuum and using a coolant hose to carry the heat into the house.  Your steel, although not great as a radiator, is cost effective. Your aluminum material would run roughly double the cost.   

[Bruce S]

Shadow;
Quick small question. In picture 009 the pic looks like you have both the heated and cold coming out of the bottom of the heater.
Is this only because it looks that way? Do you have a picture of the backside, showing the intake and exhaust better?

Heat build up, yep bigger fan(s) could help. Couldn't find how you set them up but try a larger one "pulling" the air out while leaving the other smaller pushing the air in.
As I'm sure you've read, as the heated air gets hotter it'll want to push it's way out, so giving it more help in getting out (bigger fan pulling heated air out) should help.
Of course letting it get hot and testing it come winter will be the telling tale.

NICE looking panel!!

Cheers
Bruce S

[Shadow]

Hey Bruce, Thanks for the comments.

i used the same channel metal for the upper and lower headers. The cold air from the basement comes in the bottom port and flows along the double wide bottom header and up each channel to the double wide upper channel where it all flows to the left  over to the left most double channel down the left side. This double channell on the left dead ends at the bottom where it meets the cold air. It is sealed off from the other channels . So the hot air flows into the house.

I am currently using a 5 inch 7 blade muffin fan in the basement about 15 feet away . It goes across the bedroom cieling then 5 feet down the wall . So draws cool air about 3 feet off the floor. (thats all the 5 inch pipe I had on hand)

 the hot air runs across the first bedroom with a 3 inch pipe dropped down about center of the room, then 5 inch continues on about 12 feet to next bedromm then reduces to a 3 inch pipe at the end.

 So now I added a second fan , same thing 5 inch inside the hot air just inside the wall about a foot from the solar heater.

 I think that might be the answer..but  by 10;30 it was so hot in the girls rooms I had to go throw a blanket over the heater for the day!.. The fan still kept running until about 4 pm!  Go figure.. It was soo hot under that blanket and just never cooled down enough to kick the fan off.